The present invention relates to a continuous film take-up apparatus for taking up a plurality of films in succession into a film magazine.
For efficiently printing onto a photographic film in a photographic printing apparatus, the film is fed to a printer continuously from a film magazine in which a plurality of films spliced with one another using adhesive tapes are wound on a reel.
For taking up the films into the film magazine, a conventional method includes splicing the films by hand and manually winding the films into the film magazine. However, such manual operations of splicing films and taking them up in the film magazine require considerable amounts of time and labor and efficiency cannot be increased.
We, the inventors of the present invention, have developed and proposed a continuous film take-up apparatus for feeding a plurality of films in succession to a photographic printing apparatus. The continuous film take-up apparatus allows the films to be continuously wound on a reel without splicing as with the conventional manner. In particular, the leading end of each film is placed not over but under the trailing end of a preceding film so that the films can be fed by friction out of the film magazine.
The continuous film take-up apparatus does not provide for overlapping the films with the leading end of a film placed under the trailing end of the preceding film automatically. This requires a manual operation which is not efficient.
Even if the continuous film take-up apparatus satisfying the abovesaid demands becomes attainable, it would be necessary to know in advance the maximum overall length of film which can be fed into the film magazine.
If a mechanism is provided to measure the overall film length precisely, such mechanism will increase cots and complicate operation. What is needed is to know only a limit amount over which the film cannot be wound further. There is no need to know changes in the amount of film taken up moment by moment.
An object of the present invention is to provide a continuous film take-up apparatus having a film take-up amount detection means which is economical and simple in structure, and can detect a limit over which the film cannot be wound further.